Continuous autofocusing eyewear

Abstract

Autofocusing eyewear for correcting eye accommodative dysfunctions includes a pupil tracking VOG (video-oculography) system to determine location of the pupils, a focus-tunable lens and a controller to focus the lens based on the position of the pupils.

The invention claimed is: 
     
       1. A method of providing passively improved vision to a user, the method comprising the steps of:
 providing an eyewear device, said device comprising:
 an imaging subsystem; 
 an illumination subsystem; 
 a set of adjustable lenses; and 
 a controller connected to the imaging sub system, to the illumination subsystem, and to the set of adjustable lenses; 
 
 calculating, by the controller, a histogram of pixel intensities from an image of the user's eyes captured by the imaging subsystem; 
 adjusting, by the controller, an intensity of the illumination system to use an intensity by which the user's eyes are clearly discernible by the imaging subsystem; 
 obtaining, by the controller, an estimate of viewing angle for each of the user's eyes, wherein the controller obtains the viewing angle of each of the user's eyes by the steps of:
 receiving a pupil image from the imaging subsystem; and 
 obtaining an estimate of viewing angle from the features of the pupil image; 
 
 calculating, in the controller, an estimated viewing distance from the estimated viewing angles of both of the user's eyes; and 
 adjusting, by the controller, the focal power of each lens in the set of adjustable lenses to provide improved vision in each of the user's eyes based on a predetermined correction factor for the estimated viewing distance. 
 
     
     
       2. The method of  claim 1 , wherein the eyewear device is an eyeglass frame. 
     
     
       3. The method of  claim 1 , wherein the imaging subsystem comprises a camera system connected to the controller and adapted to provide the pupil image of each of the user's eyes to the controller. 
     
     
       4. The method of  claim 3 , wherein the illumination system comprises an infrared light emitting diode for each eye. 
     
     
       5. A self-adjusting vision system comprising:
 an eyeglass frame; 
 an imaging subsystem attached to the eyeglass frame; 
 an illumination subsystem attached to the eyeglass frame; 
 a lens subsystem attached to the eyeglass frame; 
 a controller attached to the eyeglass frame and electronically connected to the imaging subsystem, the lens subsystem and the illumination subsystem; and 
 a power supply attached to the eyeglass frame and electronically connected to the controller; wherein the controller is programmed to:
 calculate a histogram of pixel intensities from an image of the user's eyes captured by the imaging subsystem; 
 adjust an intensity of the illumination system to use an intensity by which the user's eyes are clearly discernible by the imaging subsystem; 
 obtain an estimate of viewing angle for each of the user's eyes by: (i) receiving a pupil image from the imaging subsystem; and (ii) obtaining an estimate of viewing angle from the features of the pupil image; 
 calculate an estimated viewing distance from the estimated viewing angles of both of the user's eyes; and 
 adjust the focal power of each lens in the set of adjustable lenses to provide improved vision in each eye of the user's eyes based on a predetermined correction factor for the estimated viewing distance. 
 
 
     
     
       6. The self-adjusting vision system of  claim 5 , wherein the imaging subsystem comprises two CMOS sensors, each positioned to capture an image of an eye when the eyeglass frame is worn by a user. 
     
     
       7. The self-adjusting vision system of  claim 5 , wherein the illumination subsystem comprises four wide-angle infrared light sources, wherein two of said light sources are adapted to illuminate each eye. 
     
     
       8. The self-adjusting vision system of  claim 7 , wherein the infrared light sources are light emitting diodes. 
     
     
       9. The self-adjusting vision system of  claim 5 , wherein the lens subsystem comprises two adjustable lenses. 
     
     
       10. The self-adjusting vision system of  claim 9 , wherein the lens subsystem comprises an electro-mechanically adjustable lens or a liquid crystal lens. 
     
     
       11. The self-adjusting vision system of  claim 9 , wherein the self-adjusting lenses are focus tunable Alvarez lenses. 
     
     
       12. The self-adjusting vision system of  claim 9 , wherein the self-adjusting lenses are liquid crystal lenses. 
     
     
       13. The self-adjusting vision system of  claim 9 , wherein the lens subsystem further comprises a fixed lens.